This invention relates to reactive resin mixtures of organic polyisocyanates, organic polyepoxides and special catalysts and to a process for the production of moldings using these mixtures.
Plastics containing isocyanurate and oxazolidinone groups are known. They may be produced by polymerization of polyfunctional 1,2-epoxides with polyisocyanates in the presence of hardening catalysts (DE-OS 3,323,153, EP 0 130,454, DE-OS 3,323,084, DE-OS 3,323,123). Suitable hardening catalysts are, for example, tertiary amines and imidazoles, also onium halides and borates. Suitable thermolatent activators are addition complexes of boron trihalides with tertiary amines, imidazoles and morpholines.
The pot life of such mixtures may be lengthened somewhat by using tertiary amines of imidazoles deactivated by addition of electron acceptors such as 7,7,8,8-tetracyanoquinodimethane. All of these activator systems are expensive, difficult to handle or not sufficiently latent to lengthen the relatively short pot life of the reactive resin mixture enough to facilitate processing.